A heating-cartridge normally has a generally cylindrical metallic shell, a rigid insulating body in the shell having a longitudinally directed end face, and a heating conductor imbedded in the body and having a pair of ends. This heating wire is normally of the resistive type that is formed into a coil between its ends. Respective highly conductive wires imbedded in the body are connected to the ends and have insulated portions that project from the face of the body.
Such a heating cartridge is mounted in a blind bore of a piece of process equipment as described in copending application 426,100 filed Sept. 28, 1982 (now abandoned), typically a machine used in molding thermoplastic synthetic resins. Its wires extend to a termlnal board where they are connected to feed conductors or terminals.
As such a heating device is subjected to considerable thermal stress, it has a limited service life. Replacement is an onerous task involving disconnecting the wires and pulling out the nonworking cartridge, then inserting a new cartridge and connecting up its conductors.